The 25-year-old is reportedly a transfer target of Gunners boss Arsene Wenger, who plans to make a bid for the Brazilian in January.
The striker's agent Teodoro Fonseca has claimed that the Premier League side have previously been in contact with the Portuguese club, but revealed that Arsenal will need to meet Hulk's €100m (£87m) release clause.
"Every year there are more clubs interest in Hulk and I am also aware that there are clubs from outside the Premier clubs interested," Fonseca told A Bola.
"This Arsenal rumour is news to me but it is true that there has been contact before but nothing happened.
"But I speak often with Porto and the figures have not changed. He will only be sold if someone pays the €100m so this figure of £23m that has appeared would not be considered."
Arsenal's current record transfer fee is £16m, which was spent on bringing Andrey Arshavin to the Emirates.